A nearly 50-year-old de Havilland Canada DHC-6 Twin Otter was operating parachutist dropping flights out on Fentress Airpark (Texas, USA) on this day in aviation history in 2016. Ten successful flights had already been completed under FAA Part 91: General Aviation - Skydiving.
The aircraft after being bought for part out (© Gravitas Aviation)
After the parachutist had successfully exited the aircraft descended towards Fentress Airpark for the eleventh landing of the day. Visual Meteorological Conditions prevailed;
Wind - 140º at 15 knots, gusting at 21 knots
Clouds - Broken at 7000 feet AGL
Temp. - 26ºC
Dewp. - 12ºC
Visibility - 10 miles
QNH - 30.03 inHg (1018 hPa)
As the landing was planned at runway 22, there would be a crosswind component for the landing, which would be 14.8 knots. The previous ten landings had been completed in similar conditions, with gusty winds. After an uneventful descent and final approach (VFR, straight in), the aircraft touched down on the 3200 x 50 feet asphalt runway. As the aircraft was de-rotated and the nose wheel touched down the aircraft became unstable and veered to the left. The pilot flying applied right rudder and added power to abort the landing. The actions taken by the pilot could not stop the aircraft from departing the paved area of the runway to the left. The left wing impacted a tree, spinning the aircraft 180 degrees to the left, after which it came to a stop. The crew shut the aircraft down and evacuated the aircraft unharmed.
The aircraft shortly after the accident, note the damaged wing (© FAA) The left wing of the aircraft was substantially damaged, the damage was so extensive that the aircraft was written off as damaged beyond repair. At the time of the accident, the aircraft (which was manufactured in 1966) had accumulated 53624 flight hours.
An investigation into the accident was carried out by the National Transportation Safety Board (NTSB). In their report, published on the 1st of June, 2016, they concluded that the probable cause(s) of this accident was:
"The pilot's failure to maintain directional control during the aborted landing in gusty crosswind conditions, which resulted in a runway excursion and a collision with a tree."
The aircraft is being readied for road transport for part-out (© Skydive San Marcos)
The NTSB report, which served as the source for this blog can be accessed by clicking on the .pdf file below;